Fallout from advertisers has begun to escalate over conservative talk show host Rush Limbaugh's reference to a Georgetown law student as a "slut" and a "prostitute" for her stance on the contraception debate.

As a result, seven companies who advertise on Limbaugh's daily talk show have decided to pull their ads. They include Quicken Loans, online data backup provider Carbonite, Sleep Train and Sleep Number mattress retailers, LegalZoom and ProFlowers.

Limbaugh made the comments after Sandra Fluke testified before a panel of congressional Democrats in support of President Obama's policy of mandating free contraceptives to all female employees, even at religious institutions (such as hospitals and colleges) that object to such services. Religious institutions were outraged by the policy, setting the stage for a national debate on religious liberty.

After several politicians called on Limbaugh to take back his comments, one of the nation's most popular radio host issued an apology, and said he did not believe his comments were serious enough to reach a "presidential level."

President Obama contacted Fluke by phone on Friday to offer his support.

"For over 20 years, I have illustrated the absurd with absurdity, three hours a day, five days a week. In this instance, I chose the wrong words in my analogy of the situation. I did not mean a personal attack on Ms. Fluke," Limbaugh said in his statement.

"My choice of words was not the best, and in the attempt to be humorous, I created a national stir. I sincerely apologize to Ms. Fluke for the insulting word choices."

Nonetheless, Limbaugh stood firm in his opposition to President Obama forcing insurers to provide free birth control, even if companies or institutions with religious objections choose not to participate.

"I think it is absolutely absurd that during these very serious political times, we are discussing personal sexual recreational activities before members of Congress," Limbaugh also said in his statement. "I personally do not agree that American citizens should pay for these social activities. What happened to personal responsibility and accountability? Where to we draw the line?"

Cardinal Timothy Dolan, one of America's foremost Catholic leaders and a staunch opponent of the administration's position on contraception, reportedly said comments against the White House or their supporters should not be "pugnacious."

"Whatever we do, and however strongly we feel, we do it charitably, we do it civilly," the New York Daily News reported Dolan saying after Sunday morning mass at St. Patrick's Cathedral.

"We don't judge the motives of other people," Dolan added. "We just try, in a confident, peaceful, inviting way, to make our position felt, to invite other people to respect it."

Clear Channel Communications, which hosts Limbaugh's popular and long-running show, issued a statement of support over the controversy.

"The contraception debate is one that sparks strong emotion and opinions on both sides of the issue," the company said in a statement. "We respect the right of Mr. Limbaugh, as well as the rights of those who disagree with him, to express those opinions."